Systems and methods comprising permanganate for improved preservation and yield of crops and related goods

ABSTRACT

Preferred embodiments of the present invention comprise the optional application of concentrations of an aqueous permanganate solution, such as an approximately 0.01% to approximately 50% liquid permanganate solution and preferably comprising approximately 20% sodium permanganate dosed at approximately 1 ppm to approximately 100 ppm to harvested sugar crops, such as sugarcane, sugar beets, and sweet sorghum, at one or more of the sugar processing steps for the crops. The steps where the liquid sodium permanganate may optionally be applied include at a sugar crop cutting step, a sugar crop conveying step, a sugar juice extraction step, a sugar juice clarifying step, and a clarifier muds filtration step. The application of liquid sodium permanganate in the processing of sugar from sugar crops results in reduced equipment fouling, reduced loss in juice purity, reduced scale formation, decreased turbidity in clarified juices, increased sugarcane processing rates, reduced sugar crop production costs, increased sugar product yield, and increased production capacity.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of nonprovisional patent applicationU.S. Ser. No. 16/257,950 filed on Jan. 25, 2019, which claims thebenefit of provisional patent application U.S. Ser. No. 62/697,708 filedon Jul. 13, 2018, which is incorporated by reference herein for allpurposes.

FIELD OF THE INVENTION

The present invention relates to systems and methods for improving sugaryield and production efficiency. More specifically, the presentinvention concerns the application of concentrations of a permanganate,such as liquid sodium permanganate, to harvested sugar crops, such assugarcane, sugar beets, and sweet sorghum, during processing of thecrops for the purpose of increasing sugar yield and productivity.

BACKGROUND OF THE INVENTION

The main objective of processing sugar crops is to extract sugar, and itis important to not only maximize sugar extraction but to also minimizesugar degradation during processing. Post-harvest sugar deterioration isa well-known problem. Mechanical harvesting of sugar crops, annualfreezes, and extended storage of crops prior to processing (due to sugarmill shutdowns, long term cut-to-crush times, etc.) may lead topost-harvest sugar crop deterioration due to microbial contamination,which affects both sugar crop growers and sugar mills.

It is also important to maximize mill production efficiency byminimizing downtime and capacity constraints brought about by cleaningoperations. Such operations take away from the productivity of the milland incur costs for cleaning chemicals and labor.

Sugar crop processing, sugar beet processing, and sugar sorghumprocessing share many of the same equipment, processes, and problems. Inshort, these processes include the steps of: (i) extracting juice from aplant source by mechanically breaking up the plant structure combinedwith washing with water or thin recycle juice termed imbibition water;(ii) moving the juice through chemical and mechanical purification toseparate solids and impurities; (iii) concentrating the juice inmultistage evaporators; and (iv) vacuum boiling the concentrated juiceto crystallize the raw sugar. Sugarcane, as will be described below, isbut one of several sugar crops known to encounter similar problems andthat will also benefit from the invention.

Microbial contamination by way of microorganism invasion in sugarcanestalks occurs primarily through cut ends of the harvested stalks. Oncethe microorganisms are established in a sugar juice rich region of thesugar cane stalks the microorganisms rapidly proliferate. Leuconostocand serratia are two of the most devastating bacterial microbes, causinglarge amounts of post-harvest sucrose losses in sugarcane. As abyproduct of microbial activity, dextran and other polysaccharides aresynthesized from sucrose. In addition to the loss of sugar product tothese metabolism pathways, the byproducts also cause problems in sugarprocessing.

Sugar crop deterioration is a well-documented problem. It affects boththe cane growers and the sugar mills. Cane deterioration leads to manymechanical and operational problems in sugar mills, including poorclarification, evaporator scaling, decreased crushing rates, increasedviscosity of massecuites, crystal elongation, false grain formation, andcentrifugation difficulties. Corresponding economic losses are incurreddue to yield loss, impurities in the raw sugar product, and increasedchemical usage for cleaning of devices used in the production process.Microbial activity utilizes and deteriorates existing sugars to formproducts such as dextrans, exopolysaccharides, oligosaccharides, organicacids, ethanol, and mannitol.

Currently, microbial activity and the formation of microbial byproductsare managed by the application of biocides, dextranase, amylase,surfactants, viscosity modifiers, and other sanitation chemicals.Drawbacks of these approaches include storage and handling of hazardouschemicals, ineffectiveness of many biocides towards Leuconostoc andSerratia bacteria, high corrosion of equipment from use ofchlorine-based biocides, chlorine organic byproduct formation from useof chlorine-based biocides, the high cost of dextranase, the longresidence time required for dextranase, and the high cost and downtimeincurred by evaporator shutdowns for chemical cleaning. The sugarindustry continues to lose millions of dollars annually due to sugarlosses from sugar degradation and low-quality sugar due to degradationbyproducts. In addition, the industry also spends millions of dollars onenzymes, processing aids, equipment cleaning products, replacementequipment, and employee time lost on equipment maintenance, cleanouts,and repairs.

As a readily available, economical, and versatile oxidizing agent,permanganate (MnO₄ ⁻¹) has played a key role in hundreds of industrial,agricultural, and aqua cultural processes. Permanganate is used for themodification, purification, sanitation, cleaning, bleaching, anddeodorizing of commercial products. These commercial products includefoods, food additives, and drinking water.

Accordingly, there exists an unmet need in the art for compositions andmethods comprising permanganate for the treatment of sugar crops for thereduction of sugar mill production costs and increasing of quality sugaryield.

SUMMARY OF THE INVENTION

To resolve the aforementioned unmet need in the art, the presentinvention comprises permanganate-based systems and methods for reductionof exopolysaccharides, and reduction of bacterial growth in sugar cropprocessing. In particular, preferred embodiments of the presentinvention comprise sodium permanganate application during crop storage,sugar juice clarification, and/or at multiple steps in mill processingto reduce polysaccharide formation, sugar juice viscosity, andturbidity. The processing areas where improvements occur as a result ofthe present invention include reduced equipment fouling, reduced loss injuice purity, reduced scale formation, decreased turbidity in clarifiedjuices, and increased sugarcane processing rates. The invention resultsin reduced sugar crop processing costs, increased sugar product yield,and increased production capacity.

Preferred embodiments of the present invention comprise sodiumpermanganate (NaMnO₄) provided to sugar crops during processing, whereinthe preferred applied dosage of 20% sodium permanganate solution has arange of 1 parts per million (“ppm”) to 100 ppm. When applied to sugarcrops, such as sugarcane, sugar beets, and sweet sorghum, sodiumpermanganate significantly reduces microbial contamination andexopolysaccharide contamination. This effectively reduces sucrose lossesand processing costs.

The present invention is unique in several respects and itadvantageously resolves several major issues in sugar processingtechnology, wherein sodium permanganate may be used: (i) to degradeoligosaccharides and polysaccharides that are either native to the sugarcrop or formed due to microbial activity (e.g., dextrans andexopolysaccharides); (ii) as a disinfection compound during sugarmilling and processing to reduce exopolysaccharide formation and microbegrowth; (iii) to enhance clarification and reduce turbidity in sugarsolutions; (iv) to reduce viscosity problems in sugar solutions; (v) asa substitute to biocides and other sanitation products; (vi) to reducescheduled equipment cleaning and maintenance (e.g. de-scaling); and(vii) to reduce loss in juice purity.

A preferred embodiment of the present invention comprises:

A method for improving production of sugar from sugar crops, the methodcomprising the steps of:

-   -   (i) preparing a sugar crop to form a prepared sugar crop for        milling in a sugar mill to extract sugar therefrom;    -   (ii) optionally applying a first application of an aqueous        permanganate solution to the prepared sugar crop;    -   (iii) conveying the prepared sugar crop to the sugar mill;    -   (iv) optionally applying a second application of the aqueous        permanganate solution to the prepared sugar crop as the prepared        sugar crop is being conveyed to the sugar mill;    -   (v) processing the prepared sugar crop in a tandem mill of the        sugar mill to form a processed sugar crop;    -   (vi) optionally applying a third application of the aqueous        permanganate solution to the processed sugar crop at the tandem        mill and/or to the imbibition water used to wash the processed        sugar crop at the tandem mills;    -   (vii) forming cush cush and extracting sugar juice from the        processed sugar crop to form extracted sugar juice;    -   (viii) optionally applying a fourth application of the aqueous        permanganate solution to the cush cush;    -   (ix) optionally applying a fifth application of the aqueous        oxidant solution comprising a permanganate to the extracted        sugar juice;    -   (x) clarifying the extracted sugar juice in a clarifier to form        clarified sugar juice and clarifier muds;    -   (xi) filtering the clarifier muds to form a clarifier muds        filtrate; and    -   (xii) optionally applying a sixth application of the aqueous        permanganate solution to the clarifier muds filtrate being        recycled;

wherein at least one of the optionally applying steps (ii), (iv), (vi),(viii), (ix), and (xii) is performed; and

wherein the aqueous permanganate solution comprises approximately 0.01%to approximately 50% by weight permanganate.

In preferred embodiments of the present invention, the aqueouspermanganate solution preferably comprises approximately 10% toapproximately 30% sodium permanganate and most preferably 20% sodiumpermanganate which is dosed at concentrations ranging from approximately1 parts per million to approximately 100 parts per million.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an illustration showing basic steps of sugarcane versus sugarbeet processing.

FIG. 2 is an illustration showing sugar cane processing steps.

FIG. 3 is a graph showing microbe growth reduction in sugar cropstreated in accordance with preferred embodiments of the presentinvention.

FIG. 4 is a photograph showing dextran formation in sugarcane juice thatwas untreated as compared to sugarcane juice that was treated inaccordance with preferred embodiments of the present invention.

FIG. 5 is a photograph showing the coagulation effects of permanganatein sugar juice.

FIG. 6 is a graph showing clarifier turbidity results at Mill #1comparing treatments without liquid permanganate (0 ppm) and with liquidpermanganate (approximately 10 ppm) provided in accordance withpreferred embodiments of the present invention.

FIG. 7 is a graph showing clarifier turbidity results at Mill #1comparing treatments without liquid permanganate (0 ppm) and with liquidpermanganate (approximately 15 ppm) provided in accordance withpreferred embodiments of the present invention.

FIG. 8 is a graph showing sugarcane juice purity percentages forcomposite juice samples in a crusher that were not treated with liquidpermanganate.

FIG. 9 is a graph showing sugarcane juice purity percentages forcomposite juice samples in a crusher that were treated with liquidpermanganate provided in accordance with preferred embodiments of thepresent invention.

FIG. 10 is a graph showing crusher juice vs mixed juice purity withoutliquid permanganate treatment at Mill #3.

FIG. 11 is a graph showing crusher juice vs mixed juice purity withliquid permanganate treatment at Mill #3 provided in accordance withpreferred embodiments of the present invention.

FIG. 12 is a graph showing crusher juice vs mixed juice purity withoutliquid permanganate treatment at Mill #4.

FIG. 13 is a graph showing crusher juice vs mixed juice purity withliquid permanganate treatment at Mill #4 provided in accordance withpreferred embodiments of the present invention.

FIG. 14 is a graph showing effects of liquid permanganate treatment ondaily juice purity losses from crusher to mixed juice at Mills #3, 4,and 5 provided in accordance with preferred embodiments of the presentinvention.

FIG. 15 is a graph showing effects of liquid permanganate treatmentprovided in accordance with preferred embodiments of the presentinvention, as compared to the absence thereof, on juice purity incrushers at all mills located in Louisiana where testing occurred.

FIG. 16 is a photograph of evaporator tubes after two weeks ofconventional juice treatment at Mill #5, the tubes showing hard scale.

FIG. 17 is a photograph of evaporator tubes after two weeks ofapplication with liquid sodium permanganate treatment provided inaccordance with preferred embodiments of the present invention at Mill#5, the tubes showing reduced hard scale.

FIG. 18 is a photograph of an evaporator cover after two weeks ofconventional juice treatment at Mill #5, the covering showing hardscale.

FIG. 19 is a photograph of evaporator cover after two weeks ofapplication with liquid sodium permanganate treatment provided inaccordance with preferred embodiments of the present invention at Mill#5, the tubes showing reduced hard scale.

FIG. 20 is a graph showing the thermal conductivity of various deposits.

FIG. 21 is a photograph showing fouling of a cush cush drag treated withdextranase, a biocide, and amylase, absent treatment with liquid sodiumpermanganate.

FIG. 22 is a photograph showing reduced fouling of a cush cush dragafter 48 hours of liquid sodium permanganate treatment in the millprovided in accordance with preferred embodiments of the presentinvention.

FIG. 23 is a photograph showing a crusher inspection hatch cover treatedwith conventional chemicals, namely, dextranase, biocide and amylase.

FIG. 24 is a photograph showing a different view of a crusher inspectionhatch cover treated with conventional chemicals, namely, dextranase,biocide and amylase.

FIG. 25 is a photograph showing a crusher inspection hatch cover after24 hours of treatment with liquid sodium permanganate provided inaccordance with preferred embodiments of the present invention.

FIG. 26 is a photograph showing a crusher inspection hatch cover after48 hours of treatment with liquid sodium permanganate provided inaccordance with preferred embodiments of the present invention.

FIG. 27 is a photograph showing a crusher inspection hatch cover after120 hours of treatment with liquid sodium permanganate provided inaccordance with preferred embodiments of the present invention.

FIG. 28 is a photograph showing a rotary screen treated withconventional dextranase, biocide and amylase.

FIG. 29 is a photograph showing reduced fouling of a rotary screen usedduring processes that included liquid sodium permanganate treatmentprovided in accordance with the present invention.

FIG. 30 is a photograph showing a knives section of a sugar millingprocess, the knives shown after treatment with liquid sodiumpermanganate provided in accordance with preferred embodiments of thepresent invention.

FIG. 31 is a photograph showing another view of a knives section of asugar milling process, the knives shown after treatment with liquidsodium permanganate provided in accordance with preferred embodiments ofthe present invention.

FIG. 32 is a diagram showing sampling locations (i)-(vi) in a sugarmilling process, as further described herein, where samples were takento test for presence of manganese into the sugar being processed.

FIG. 33 is a graph showing manganese transport in a sugar mill.

FIG. 34 is a diagram showing optional locations (i)-(vi) for applicationof sodium permanganate in accordance with preferred embodiments of thepresent invention in a sugar milling process, as further describedherein.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention may be susceptible to embodiment indifferent forms, there are described herein in detail, specificembodiments with the understanding that the present disclosure is to beconsidered an exemplification of the principles of the invention, and isnot intended to limit the invention to that described herein.

FIG. 1 shows the basic steps of sugarcane versus sugar beet processing.

FIG. 2 shows the basic stages of sugar crop milling. These stages are:

-   -   1. First, sugar cane is harvested and preferably cut into        billets or stalks.    -   2. Second, the sugar cane billets or stalks are washed and cut        into shreds by rotating knives.    -   3. Next, huge rollers in the milling train press the juice out        of the shredded pulp.    -   4. The juice is then clarified-by adding milk of lime and        polymers. The resulting mixture forms calcium carbonate, which        attracts the non-sugar plant materials like wax, fats, and gums        from the juice. The calcium carbonate and the other materials        are settled out in a clarifier or by filtration.    -   5. Then the juice is concentrated by removing water from the        clarified juice in multiple stages under vacuum. This allows the        juice to boil at lower temperatures to protect the sugar from        caramelization.    -   6. The concentrated juice is then crystallized by evaporating        the last portion of water under very tight controls in a vacuum        pan. Seed grain (pulverized sugar) is fed into the pan as the        water evaporates and crystals begin to form. The mixture leaves        the vacuum pan as a thick crystal mass and is sent to a        centrifuge, a large perforated basket spinning very rapidly much        like a washing machine in the spin cycle, where it is spun and        dried, thereby yielding golden raw sugar.

Sodium Permanganate for Reduction of Microbes in Sugar Juice

A preferred embodiment of the present invention comprises a blend ofpermanganate salts that is preferably manufactured as a concentratedliquid. A source of such a liquid sodium permanganate compound is CamsCorporation, located in Peru, Ill., United States of America. CamsCorporation manufactures and markets its liquid sodium permanganateproduct for use in the sugar industry under the brand name SucrOx™liquid permanganate. It is contemplated that potassium permanganate mayalso be used as a substitute for sodium permanganate.

Permanganate is a strong oxidizing agent. As an oxidant, permanganatereacts quickly with inorganic, organic, and biological compounds. Inorganic chemistry, permanganate is considered a broad-spectrum oxidantbecause of the many organic functional groups that it reacts with. Inparticular, permanganate has an affinity for cleaving organic double andtriple bonds, making it extremely useful in industrial, municipal, andenvironmental bleaching and purification applications.

An investigation of biocide use in sugar factories and whether thebiocides are effective for the prevention of bacterial sugar loss wasperformed. Of special interest to sugar mills is the elimination ofleuconostoc bacteria. Leuconostoc metabolizes sucrose producing dextranand other polysaccharides that interfere with down-stream sugarprocessing. Research shows that traditional biocides, such as sodiumhypochlorite, humulone, and carbamate compounds, are not effective forcontrolling leuconostoc, create hazards in storage and handling, and/orcreate undesirable reaction byproducts.

However, control of leuconostoc and serratia in sugarcane juice isachieved using liquid sodium permanganate at low parts-per-milliondosages. In particular, as shown in FIG. 3, adding liquid sodiumpermanganate at the second mill to the cush cush (see FIG. 2) and at thesixth mill (id.) at approximately 3 ppm and approximately 6 ppm dosages,respectively, achieves a 2-log reduction in bacteria.

Sodium Permanganate Use for Turbidity Reduction in Sugar Juice

As shown in FIG. 3, sugarcane juice clarity improves and dextranformation is reduced when, for example, approximately 10 ppm of liquidsodium permanganate is applied to the juice. High-performance liquidchromatography (“HPLC”) sugar analysis revealed three additionalimportant results: (i) liquid sodium permanganate treatment of sugarcane juice lowers a 15-day average fructose/glucose ratio byapproximately 30%, which is an indication of reduced bacterial activityand reduced dextran production; (ii) essentially no mannitol is detectedin liquid sodium permanganate treated samples of sugar cane juice; and(iii) mannitol is detected on approximately six out of fifteen days insugar cane juice samples that are not treated with liquid sodiumpermanganate. Leuconostoc metabolizes sucrose via a dextransucraseenzyme to form fructose and glucose, followed by rapid metabolism ofglucose to form dextran. Fructose is metabolized to a lesser degree toform mannitol. A high fructose/glucose ratio plus the presence ofmannitol is indicative of a leuconostoc infestation of the cane. Theobserved decrease in the fructose/glucose ratio and levels of mannitolas described above indicate that embodiments of the present inventionare inhibiting leuconostoc activity.

A reaction byproduct of liquid sodium permanganate is manganese dioxide(MnO₂). Manganese dioxide is a small particle, with high surface areaand charge, which acts as a coagulation aide in clarifiers (FIG. 5).Additionally, FIG. 5 shows an improvement in floc formation and claritywith progressively higher dosages (3 ppm, 6, ppm, and 10 ppm) of liquidsodium permanganate combined with sugar cane juice samples.

Improvements to Cane Juice Clarification—Mill #1

Several short-term evaluations to determine whether permanganatetreatment in accordance with preferred embodiments of the presentinvention would improve the performance of cane juice clarificationprocess were made. Effectiveness was determined by monitoring theclarified turbidity of the juice. A sugar mill was selected for thispurpose (“Mill #1”), in part, because Mill #1 had the capability ofoperating two identical clarifiers in parallel, allowing Mill #1 staffto evaluate permanganate treatment in one clarifier while using thesecond as an untreated control unit.

While this was a good set-up for data collection and comparison, it didhave one significant limitation. To isolate one clarifier, thepermanganate injection point had to be located after the juice flowdivides into two separate clarifier inlets. Therefore, permanganatetreatment of the cane juice was provided only seconds before theclarifier, shortening the reaction time. In prior tests at other sugarmills, the permanganate was applied much earlier in the process.

At Mill #1, liquid sodium permanganate was fed for 18 days during Mill#1 82-day processing run. The application rate was between approximately10 ppm and approximately 15 ppm liquid permanganate.

Increases in Sugar Yield—Mill #2

In Mill #2, liquid sodium permanganate was applied during sugarcanecrushing season with a focus on biological control impacts. Theapplication point was into the plant cush cush in low, controlleddosages of approximately 3 ppm and approximately 6 ppm of liquid sodiumpermanganate. In a subsequent year, Mill #2 used permanganate again byways of an innovative treatment technique. In addition to treating thecush cush, Mill #2 used a second location by spraying liquid sodiumpermanganate onto sugarcane billets as they were stacked in a yard. Asan alternative to spraying, the billets may be dipped or soaked inliquid sodium permanganate solution. Specifically, the billet surfaceswere treated, sealing the cuts to the stalk and minimizing sugar loss.The liquid sodium permanganate was fed for 74 days of Mill #2's 102-dayrun. The average usage rate was approximately 6 ppm of liquid sodiumpermanganate.

During the following year's harvest season, additional testing on theclarifier effectiveness was conducted while feeding permanganate earlierin the process, giving it a longer reaction time. A feed ofapproximately 10-15 ppm of permanganate was added to the cane in theyard and to the sugar juice at the cush cush. This testing was performedfor 40 days.

Mill #3

Mill #3 used liquid sodium permanganate as a full plant processing aidbeginning on the first day of the season. At this site, liquid sodiumpermanganate was sprayed onto cane billets as they were conveyed tomilling knives as well as to cush cush. Liquid sodium permanganate wasfed for 111 days, the full mill run.

Mill #3 processed significant amounts of cane and the initial liquidsodium permanganate application rate was approximately 15 ppm of liquidsodium permanganate. Later, the feed rate was increased to nearlyapproximately 30 ppm and operational and mechanical aspects of Mill #3continued to improve. At the end of the harvest season, whenpolysaccharide levels coming from the field are very high, the liquidsodium permanganate feed was increased to as high as approximately 100ppm of liquid sodium permanganate. Over the full run at Mill #3, theliquid sodium permanganate application rate was calculated to beapproximately 30 ppm on average.

The summarized results from the aforementioned mills is reported inTable 1 below, wherein the liquid sodium permanganate is provided underthe SucrOx™ brand.

TABLE 1 Summary of Sugarcane Mill Field Trials Days Average Tons LbsSugar Mill Days SucrOx ™ SucrOx ™ Cane Produced # Grinding Fed DosageFeed Location Ground (Millions) 1 82 18 6 ppm Clarifier 4 days, cushcush 21 days 880 207 2 102 74 15 ppm Cush cush and billets sprayed 74days 1650 410 3 111 111 30 ppm Knives and cush cush for 111 days 1476336

Discussion Regarding Sugar Mill #1

In two clarification trials run at Mill #1, two different liquid sodiumpermanganate dosages were used. A first test applied approximately 10ppm liquid sodium permanganate and the second test applied a higher,approximately 15 ppm dosage. In both trials, the clarifier that wastreated with liquid sodium permanganate produced lower effluentturbidities than the untreated clarifier. Further, the clarifier thatwas treated with approximately 15 ppm had the highest turbidityimprovement. It should be noted that both tests were run immediatelyafter plant shut-downs so there is an initial acclimation period foreach, but eventually both clarifiers reached a steady state, with minorhourly variations. In Trial 1 (see FIG. 6), the turbidity of theuntreated clarifier reached approximately 180 Nephelometric TurbidityUnits (“NTU”) and the treated clarifier was 150 NTU. In Trial 2 (seeFIG. 7), the untreated clarifier nearly achieved 200 NTU, but the liquidsodium permanganate treated clarifier again ran at 150 NTU.

Discussion Regarding Sugar Mill #2

During the following year's harvest season, Mill #2 began feeding sodiumpermanganate earlier in the process and at multiple locations. Inaddition to treating the cush cush, the plant used a second location,spraying sodium permanganate onto sugarcane billets as they were stackedin the yard. The intent was to treat the billet surfaces, sealing thecuts to the stalk and minimizing sugar loss. The permanganate was fedfor 40 days of Mill #2's 102-day run. The average usage rate wasapproximately 6 ppm of sodium permanganate (SucrOx™). Under thistreatment scenario, the permanganate levels to both clarifiers wereequal. With an additional 10 to 40 minutes of reaction time and mixingprovided, both clarifiers saw significantly lower turbidities whenpermanganate was being fed; clarifier with permanganate had 52-108 NTU,versus clarifier without permanganate had 205-220 NTU.

The innovative treatment approach at Mill #2 provided additional andunexpected insight into the positive impact of liquid sodiumpermanganate treatment. Cane juice purity was recorded at Mill #2 duringeach crop processing run and, in particular, compared crusher puritiesat 7:00 am and at 3:00 am. It was generally accepted that cane processedat 3:00 am would always comprise lower purity than the cane processed at7:00 am. An explanation for this seems to be that the cane processed at3:00 am had entered the yard during the day, with some of the canediverted to a storage stack. The stacked cane was only processed whendeliveries of harvested cane had ended for the day. Further, when thestacked cane was used, the first cane to be processed was the cane onthe top of the stack—the most recent to be delivered. By 3:00 am, thecane that had been in the yard for 12-20 hours was finally crushed.

The typically lower quality for 3:00 am cane, although slight, was truein other tests when the cane had not been treated with liquid sodiumpermanganate. See FIG. 8. However, at Mill #2, when the cane billetsentering the yard had been sprayed with liquid sodium permanganate, thedata was different. The stacked cane, processed at 3:00 am, ran a higherpurity than the freshly harvested, unsprayed cane that was crushed at7:00 am. See FIG. 9.

Discussion Regarding Juice Purity at all Mills

When comparing results over the 2016, 2017 and 2018 harvest seasons foradditional Mills #3, 4, and 5, it was observed that there was improvedjuice purity when liquid sodium permanganate was employed. Sugar purity(wt. % pol vs. wt. % brix) is measured daily by mill personnel atmultiple locations in the milling process. There is consistently a lossof purity from the start to the end of the extraction process. The juicepurity typically decreases across the mills by as much as 1-2% or more.However, as noted in graphs 7, 8, 9 and 10, the sugar purity loss isreduced when liquid sodium permanganate (SucrOx™) is used preferably atdosages of at least 10 ppm. See FIGS. 10-13.

One-way analysis of variance (“ANOVA”) was performed on daily juicepurity readings for entire crop seasons with and without liquid sodiumpermanganate use at Mills #3, 4, and 5. The difference between crusherjuice at the start of the extraction and the mixed juice afterextraction steps is plotted in FIG. 14. On average, sugar purityimproved by 0.8% for the crops treated with liquid sodium permanganate.The 95% confidence intervals indicate that the improvement associatedwith SucrOx™ is statistically significant.

Juice purities from all area mills for 2017-2018 YTD crops are shown inFIG. 15. ANOVA analysis was performed on year-to-date purities. Becausethere are fewer data points, the confidence intervals are wider. Thesame trend is observed—reduced purity loss when liquid sodiumpermanganate is used.

Evaporator Heat Transfer

At Mill #3, the addition of liquid sodium permanganate during the 2017harvest season resulted in significantly reduced downtime and chemicalcosts for evaporator cleaning.

During a “normal” season, Mill #3 took evaporators off-line fordescaling and cleaning every 11-12 days (see Table 2 below, 2015 and2016 data). In 2017, with liquid sodium permanganate treatment, the timebetween cleanings was nearly doubled to 22 days. Mill #3 set a Mill #3production record for the average tons of cane processed each day, andfor the total tons of cane processed for the year.

TABLE 2 Mill #3 Cleanings With and Without SucrOx ™ Liquid PermanganateTreatment Not SucrOx SucrOx Treated Cane Treated Crop Year 2015 20162017 Total Tonnage 1,280,595 1,229,166 1,476,935 Number of Days 98 93111 Number of Washouts on #1 Set 9 8 5 Days per Washout #1 Set 11 12 22

Other mills that used liquid sodium permanganate observed that theevaporator scale was much softer and more easily washed out than whenliquid sodium permanganate was not used. As a result, there was lowerusage of caustic and phosphoric acid cleaning chemicals.

Mill #4 is the only mill in Louisiana which utilizes cold lime treatmentof the mixed juice. The other mills that tested liquid sodiumpermanganate utilized hot lime of the mixed juice. It is theorized thatthe fouling and scaling is different because of the difference inliming. Regardless, these mills also saw improvements in the evaporatorscaling. FIGS. 16-19 show the evaporator at Mill #5. The evaporator setsat Mill #5 are routinely cleaned every 2 weeks. Under their conventionalprogram (dextranase, amylase, carbamate), the scale throughout theevaporator body was very hard. See FIG. 16. When Mill #5 tests includedliquid sodium permanganate provided in accordance with the presentinvention, the very hard scale on evaporators was eliminated. A softsludge was predominant throughout the evaporator body. See FIG. 17. Thissoft scale could be cleaned off more easily and required much less acidto clean. Similar results with evaporator cleanliness were observed atall 4 mills that fed SucrOx™ in 2018.

There are two theories regarding liquid sodium permanganate treatmentand improved evaporator performance. One theory is that improved millcleanliness when using liquid sodium permanganate helps to reduce filmformation caused by dextran, polysaccharides, and other organics. Theseorganic films have a significantly lower thermal conductivity thaninorganic scalants such as calcium carbonate, calcium sulfate, calciumphosphate, and iron oxide. When films insulate the exchange surfaces,heat transfer is reduced, necessitating cleaning. See FIG. 20. The othertheory is that improved removal of inorganics, and especially silica,reduces the loading and scaling rate of the evaporators.

Impact on Mill Cleanliness and Fouling

When using liquid sodium permanganate, milling equipment is noticeablycleaner than with the current processing aids used in sugar mills.Improved cleanliness has been observed throughout treated areas,including knives, cush cush drag, crusher and other mills, rotaryscreens, semi-wet deck surfaces, and evaporators.

FIG. 21 is a photograph of the cush cush area of Mill #4 withtraditional chemicals added, namely, dextranase, biocide, and amylase.FIG. 22 is taken after 48 hours while on approximately 30 ppm dosages ofliquid sodium permanganate. A noticeable decrease in the amount offouling of partially wetted surfaces of the cush cush drag is observedafter SucrOx™ is used.

FIGS. 23-27 show an inspection cover at the crusher mill of Mill #4.FIGS. 23-24 show a baseline from the Mill #4 crusher with conventionalchemicals added, namely, dextranase, biocide and amylase. FIGS. 25-27show reduced fouling of the inspection cover after 24 hours, 48 hours,and 120 hours, respectively, of treatment in Mill #4 with approximately30 ppm liquid sodium permanganate provided in accordance with thepresent invention.

FIGS. 28-29 show the rotary screens at Mill #4, wherein FIG. 28 showsthe rotary screen during treatment with conventional dextranase, biocideand amylase, and wherein FIG. 29 shows reduced fouling of the rotaryscreen used during processes that included liquid sodium permanganatetreatment provided in accordance with the present invention.

FIGS. 30-31 show the knives at Mill #4 after liquid permanganatetreatment provided in accordance with the present invention. Thecorresponding section was opened during a pause in processing and theknives were replaced. Contractors and Mill #4 personnel expressed thatthe system opened much cleaner. There was no slime, and the metalsurfaces were clean and free of buildup. This was much different thanprior openings. Similar results have been observed at all mills.

Tracking Manganese Through the Mill

When liquid sodium permanganate, a manganese-based compound, is fedearly in the milling process, an important question is whether itsintroduction adds any additional manganese to the final sugar product.To explore this question, samples were collected during the various testruns at the three aforementioned mills. All samples were analyzed usingStandard Method 3120 Metals by inductively coupled plasma (“ICP”).

The sampling locations were consistent from mill to mill and included:(i) crusher juice before liquid sodium permanganate addition; (ii)clarifier inlet; (iii) clarifier outlet; (iv) clarifier muds; (v)molasses; and (vi) final raw brown sugar. See FIG. 32.

For comparison at each location, untreated cane juice samples and canejuice samples treated with liquid sodium permanganate were collected,analyzed, and compared. Previous industry testing has shown that rawsugar contains low levels of various metals, including iron andmanganese. This should be expected because they are essential nutrientsfor plant growth and are present in most soils. The Cane Sugar Handbook12th Edition, Table 2.5 (Chen and Chou) reports data on 11 metalscommonly found in raw sugar, including manganese, which typically runs1-6 ppm.

For the mill samples, untreated cane juice manganese concentrationsmirrored the levels reported in the Cane Sugar Handbook 12th Edition(Chen and Chou). With liquid sodium permanganate treatment, themanganese levels decreased in the molasses and the final brown sugar. Asexpected, the manganese precipitates out of the sugar juice and depositsin the clarifier muds, where it is removed from the process. See FIG.33.

As discussed, and as shown above, sodium permanganate is an eco-friendlyoxidizing agent that has been historically used safely to purifydrinking water. Permanganate's sanitation and coagulation activity makesit an effective innocuous compound for use in sugarcane juice as adisinfectant. The biocide compounds of the prior art used by mills forjuice disinfection are either ineffective under mill processing timeconstraints, or toxic to people and the environment, or both.Permanganate's sanitation and coagulation activity make it an effectivebenign compound for use in sugarcane juice as a disinfectant, and ittargets Leuconostoc which forms exopolysaccharides that negativelyimpact sugar quality and mill processing. Application of sodiumpermanganate in accordance with preferred embodiments of the presentinvention to sugarcane juice or its byproducts may be applied at one ormore of the following locations: cane storage yard (i), cane conveyor(ii), the tandem mill and/or the imbibition water used to wash themilled crop at the tandem mills; (iii), cush cush (iv), mixed juice (v),and clarifier muds filtrate being recycled (vi). See FIG. 34. Whenliquid sodium permanganate is applied to sugar juice it may be addedbefore or after the juice is extracted in a given process step. Whenmetals, brix, turbidity, pH, ATP (adenosine triphosphate) and CFU(colony forming units) are evaluated in crusher juice, mixed juice,flash heated lime juice, clarified juice, clarification mud, bagacillo,and juice from cane billets of approximately 8 inches or whole stalks,treatment with sodium permanganate in accordance with preferredembodiments of the present invention resulted in the precipitation of amajority of residual manganese and other metals into the clarifier mud.Also, both laboratory evaluation and mill tests indicate a reduction inboth microbial growth, and sample turbidity.

While specific embodiments of the invention have been shown anddescribed, it is envisioned that those skilled in the art may devisevarious modifications without departing from the spirit and scope of thepresent invention.

1. A method for improving production of sugar from sugar crops, themethod comprising the steps of: (i) preparing a sugar crop to form aprepared sugar crop for milling in a sugar mill to extract sugartherefrom; (ii) optionally applying a first application of an aqueouspermanganate solution to the prepared sugar crop; (iii) conveying theprepared sugar crop to the sugar mill; (iv) optionally applying a secondapplication of the aqueous permanganate solution to the prepared sugarcrop as the prepared sugar crop is being conveyed to the sugar mill; (v)processing the prepared sugar crop in a tandem mill of the sugar mill toform a processed sugar crop; (vi) optionally applying a thirdapplication of the aqueous permanganate solution to the processed sugarcrop at the tandem mill and/or to the imbibition water used to wash theprocessed sugar crop at the tandem mills; (vii) forming cush cush andextracting sugar juice from the processed sugar crop to form extractedsugar juice; (viii) optionally applying a fourth application of theaqueous permanganate solution to the cush cush; (ix) optionally applyinga fifth application of the aqueous oxidant solution comprising apermanganate to the extracted sugar juice; (x) clarifying the extractedsugar juice in a clarifier to form clarified sugar juice and clarifiermuds; (xi) filtering the clarifier muds to form clarifier muds filtrate;and (xii) optionally applying a sixth application of the aqueouspermanganate solution to the clarifier muds filtrate being recycled;wherein at least one of the optionally applying steps (ii), (iv), (vi),(viii), (ix), and (xii) is performed; and wherein the aqueouspermanganate solution comprises approximately 0.01% to approximately 50%by weight permanganate.
 2. The method of claim 1, wherein the sugar cropis sugar cane, sugar beets, or sweet sorghum.
 3. The method of claim 1,wherein the aqueous oxidant solution comprising permanganate is dosed inconcentrations ranging from approximately 1 parts per million toapproximately 100 parts per million.
 4. The method of claim 3, whereinthe aqueous permanganate solution comprises sodium permanganate.
 5. Themethod of claim 4, wherein the aqueous oxidant solution comprisingpermanganate is dosed in concentrations ranging from approximately 5parts per million to approximately 30 parts per million.
 6. The methodof claim 1, wherein the aqueous permanganate solution comprisespotassium permanganate.
 7. The method of claim 1, wherein at least twoof the optionally applying steps (ii), (iv), (vi), (viii), (ix), and(xii) are performed.
 8. The method of claim 7, wherein at least three ofthe optionally applying steps (ii), (iv), (vi), (viii), (ix), and (xii)are performed.
 9. The method of claim 8, wherein at least four of theoptionally applying steps (ii), (iv), (vi), (viii), (ix), and (xii) areperformed.
 10. The method of claim 1, wherein the preparing step (i)comprises a cutting of the sugar crop into billets and wherein theapplying step (ii) comprises an application of the aqueous oxidantsolution to the cut ends of the billets.
 11. The method of claim 1,wherein the aqueous permanganate solution comprises approximately 10% toapproximately 30% by weight permanganate.
 12. The method of claim 1,wherein the aqueous permanganate solution comprises approximately 20% byweight permanganate.
 13. The method of claim 1, wherein the applyingsteps (ii), (iv), (vi), and (viii) comprise the application of theaqueous oxidant solution by spraying.
 14. The method of claim 1, whereinthe applying steps (vi), (ix), and (xii) comprise the application of theaqueous oxidant solution by injection into the imbibition water of step(vi), the extracted sugar juice of step (ix), and the clarifier mudsfiltrate of step (xii), respectively.
 15. The method of claim 1, whereina purity of at least one of the extracted sugar juice, the clarifiedsugar juice, and the filtered sugar juice is improved as compared to apurity of sugar juice formed in processes where the aqueous permanganatesolution is absent.
 16. The method of claim 1, wherein a quantity ofmicrobes in at least one of the extracted sugar juice, the clarifiedsugar juice, and the filtered sugar juice is reduced as compared to aquantity of microbes in sugar juice formed in processes where theaqueous permanganate solution is absent.
 17. The method of claim 1,wherein an overall yield of sugar produced in accordance with the methodof claim 1 is increased as compared to an overall yield of sugarproduced in accordance with methods where the aqueous permanganatesolution is absent.
 18. The method of claim 1, further comprising a step(xiii) concentrating the filtered sugar juice in an evaporator, whereina heat transfer efficiency of the evaporator is improved as compared toa heat transfer efficiency of an evaporator used in processes where theaqueous permanganate solution is absent.
 19. The method of claim 1, theprocessing step (v) further comprising a use of knives to cut theprepared sugar crop and the forming step (vii) further comprising a useof a drag in connection with the cush cush, wherein a fouling and ascaling of the knives and the drag are reduced as compared to a foulingand scaling of knives and drags used in processes where the aqueouspermanganate solution is absent.
 20. The method of claim 1, wherein aturbidity of the clarified sugar juice produced in accordance with themethod of claim 1 is reduced as compared to a turbidity of sugar juiceformed in accordance with processes where the aqueous permanganatesolution is absent.